Merge "IBinder: support FLAG_CLEAR_BUF" am: 9910d9980e

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1477120

Change-Id: I8ad610798d8ca3cdababa8a9b61cc3f70f8c760d

core/java/android/os/IBinder.java

@@ -169,6 +169,15 @@ public interface IBinder {
      */
     int FLAG_ONEWAY             = 0x00000001;
 
+    /**
+     * Flag to {@link #transact}: request binder driver to clear transaction data.
+     *
+     * Be very careful when using this flag in Java, since Java objects read from a Java
+     * Parcel may be non-trivial to clear.
+     * @hide
+     */
+    int FLAG_CLEAR_BUF          = 0x00000020;
+
     /**
      * @hide
      */

core/java/android/os/Parcel.java

@@ -276,6 +276,8 @@ public final class Parcel {
     // see libbinder's binder/Status.h
     private static final int EX_TRANSACTION_FAILED = -129;
 
+    @CriticalNative
+    private static native void nativeMarkSensitive(long nativePtr);
     @CriticalNative
     private static native int nativeDataSize(long nativePtr);
     @CriticalNative
@@ -490,6 +492,14 @@ public final class Parcel {
     @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
     public static native long getGlobalAllocCount();
 
+    /**
+     * Parcel data should be zero'd before realloc'd or deleted.
+     * @hide
+     */
+    public final void markSensitive() {
+        nativeMarkSensitive(mNativePtr);
+    }
+
     /**
      * Returns the total amount of data contained in the parcel.
      */

core/jni/android_os_Parcel.cpp

@@ -90,6 +90,14 @@ void recycleJavaParcelObject(JNIEnv* env, jobject parcelObj)
     env->CallVoidMethod(parcelObj, gParcelOffsets.recycle);
 }
 
+static void android_os_Parcel_markSensitive(jlong nativePtr)
+{
+    Parcel* parcel = reinterpret_cast<Parcel*>(nativePtr);
+    if (parcel) {
+        parcel->markSensitive();
+    }
+}
+
 static jint android_os_Parcel_dataSize(jlong nativePtr)
 {
     Parcel* parcel = reinterpret_cast<Parcel*>(nativePtr);
@@ -757,6 +765,8 @@ static jboolean android_os_Parcel_replaceCallingWorkSourceUid(jlong nativePtr, j
 // ----------------------------------------------------------------------------
 
 static const JNINativeMethod gParcelMethods[] = {
+    // @CriticalNative
+    {"nativeMarkSensitive",             "(J)V", (void*)android_os_Parcel_markSensitive},
     // @CriticalNative
     {"nativeDataSize",            "(J)I", (void*)android_os_Parcel_dataSize},
     // @CriticalNative